This research was conducted to test parasite resistance or tolerance to highly aggressive broomrape races of new-improved sunflower (Helianthus annuus L.) lines and parents obtained from different origins and to determine the effect of broomrape (Orobanche cumana Wall L.) on hybrid performance of sunflower in terms of yield and yield components. A total of 38 restorer lines (Res) and 39 cytoplasmic male sterile lines (CMS) of sunflower inoculated with broomrape were planted along 4 m in length rows at Agricultural Research and Application Centre of Uludag University, Bursa, Turkey in 1998. Seven CMS, 5 Res, 8 experimental hybrid combinations and 1 commercial broomrape resistant cultivar (Sanbro) were planted in a randomised blocks design with 3 replications in 1999 and 2000. Eight experimental hybrids and parents revealed different levels of resistance to broomrape. The only Res 88/2 and 4x10 test hybrids were highly resistant to broomrape in Bursa province. There were significant differences between genotypes and year x genotype interactions in terms of plant height, head diameter, 1000-seed weight and seed weight per head. None of the tested experimental hybrids exceeded the cv. Sanbro used as control in terms of yield.